Elements of the Periodic Table
Potassium Potassium was discovered in 1807 and is an alkali metal. Its physical characteristics are a soft waxy silvery white metal which oxidizes easily. Potassium is also very reactive. It is the seventh most abundant element on earth making up 2.4 % of the earth’s crust. In nature it occurs only as ionic salt. As such, Potassium is found dissolved in seawater, and as part of many minerals. It is also necessary for the function of all living cells, and is thus present in all plant and animal tissues. Potassium is found in especially high concentrations in plant cells, and in a mixed diet, it is most highly concentrated in fruits. It can be used in potash as a fertilizer and commonly found in soil. Potassium has an atomic mass of 39.1 and has 19 protons. Sulfur Sulfur has been known to exist for centuries and it is a non-metal. Its physical characteristics are bright-yellow solid at room temperature. It melts to a blood-red liquid and when burned, it emits a blue flame. Sulfur found in hydrogen sulfide gas has familiar rotten egg odor. For example, in drinking water this smell is a result of minute releases of the gas. In its pure state, Sulfur is odorless and has many beneficial properties. It can be found in nature in meteorites, hot springs, volcanoes and natural gas. It can be used in fertilizers, matches, insecticides, and gunpowder. Sometimes Sulfur is called brimstone. Sulfur has an atomic mass of 32.07 and has 16 protons. Carbon Carbon has been known to exist for centuries and it is a non-metal. Carbon can be found free in nature as amorphous, graphite and diamond. Therefore its physical characteristics can be dense black or even clear like glass. There are many applications of Carbon. It is the 15th most abundant element in the Earth's crust, and the fourth most abundant element in the universe by mass. Carbon is present in all known life forms, and in the human body it is the second most abundant element by mass. As Carbon is the chemical basis of all known life, it is therefore an integral part to all of life processes. A use of Carbon is in graphite which is found in pencils. Diamond is used in jewelry and for cutting. Carbon has an atomic mass of 12.01 and has 6 protons. Oxygen Oxygen was discovered in 1774 and it is a non- metal. Its physical characteristics are a colourless odourless and tasteless gas and it is pale blue as a liquid. Source of Oxygen can be found in air and as a component of the ozone layer. All major classes of structural molecules in living organisms, such as proteins, carbohydrates, and fats, contain Oxygen, as do the major inorganic compounds that comprise animal shells, teeth, and bone. Oxygen is third most abundant element found in the sun and earth. In industry it is used the most for the enrichment of steel, and also used in bleach. It is required for respirations of plants and animals. Oxygen is also an integral component of water. Oxygen has an atomic mass of 16 and has 8 protons. Sodium Sodium was discovered in 1807 and is an alkali metal. Its physical characteristics are bright silvery metal that is soft and highly reactive. Sodium elemental raw form does not occur naturally on earth, but quickly oxidizes in air and is violently reactive with water. Sodium can be found abundant in the sun and stars and is the sixth most abundant element on earth. It makes about 2.6% of the earth's crust. It is found in salt and other minerals. Sodium is an essential element for all animal life and for some plant species. Sodium can be used in the glass, soap, paper, textile, chemical, petroleum and metal industry. It is used in the preparation of organic compounds. Sodium has an atomic mass of 22.99 and has 11 protons. References *Chang, Raymond. (1998). Chemistry (6th ed.).Boston, MA.: McGraw-Hill. *Oxygen. Wikipedia http://en.wikipedia.org/wiki/Oxygen *Sodium. Wikipedia http://en.wikipedia.org/wiki/Sodium *Carbon. Wikipedia http://en.wikipedia.org/wiki/Carbon *Potassium. Wikipedia http://en.wikipedia.org/wiki/Potassium *Sulfur.Wikipedia http://en.wikipedia.org/wiki/Sulfur